## 计算矩形面积 默认宽是 5
def calc_area(length,width=5):
    return length * width

def display_area(**kwargs):
    for key,value in kwargs.items():
        print(f"{key}: {value}")


print(calc_area(10, 10))
print(calc_area(10))

display_area(name="lisi",age=30,city="BeiJing")